[Reproducibility of the signal-averaged, high-pass filtered electrocardiogram]

In order to test the reproducibility of the signal-averaged electrocardiogram (SAECG) using Simson's method (high-pass filter cutoff frequency 25 Hz, orthogonal leads, recording of 133 s per lead), 121 patients were examined. In all patients, two signal-averaged ECGs were performed on the first day of the study immediately after each other, using identical electrode position. In a subgroup of 47 patients, the same procedure was repeated 3 days later. There was no difference between the mean values of conventionally calculated averaging parameters (heart rate, QRS-duration, root-mean-square voltage in the terminal 40 ms of the highly amplified and filtered QRS-complex [V40], the low amplitude signal duration under 40 microV in the terminal portion of the QRS-complex [LAS], total root-mean-square voltage of the QRS-complex), both with regard to immediate and short-term reproducibility. Thus, conventionally calculated averaging parameters are well reproducible.